A thyristor will stay conducting until the current through the device is zero (“current zero”) or perhaps slightly negative.  LLNL’s approach is to use the opticondistor (“OTV”) to force this current zero in order to force the device into an “off” state.  By combining a light-activated thyristor with an OTV, a noise-immune, high efficiency, high-power switching device can be constructed. The…

The approach is to leverage the fact that a momentary “load” equal to the power transmission line impedance, (Z0), during the transient can suppress its propagation.  Z(0) is typically a fixed impedance of several hundred ohms based on the geometry of most single wire transmission lines.

So, an isolated self-powered opticondistor (OTV) system may provide an ultrafast method of…

LLNL’s novel approach to enable MVDC power systems to operate safely is to develop a wideband gap bulk optical semiconductor switch (WBG BOSS) circuit breaker.  For higher power, efficiency and temperature operation, vanadium-doped silicon carbide (V-doped SiC) appears to be the most promising basis for WBG BOSS circuit breaker (other dopants like aluminum, boron and nitrogen may further…

LLNL has developed a novel methodology for using commercially available automated sensors and actuators which can be deployed at scale in large appliances and plug-in EVs to provide as needed electric grid stabilization capabilities. The approach comprises of a population of voltage relays with a range of setpoints that would gradually reduce load as voltage falls. More severe voltage…